(1)No plug into ear,sanitary.
(2)Charge 2 hours, can work 23 hours.
(3)Allows two speakers to speak at the same time.
(4)The channel of all the receivers can be adjusted together by transmitter.
(5)One click to turn off all receivers.
(6)One click to make all the receivers mute.
(7)Can be used worldwide. (8)Weights only 18g. (9)Easy to charge by many choices.